Page 39 - SP015 Past Years PSPM Chapter 6 -14 Ver 2020

PSPM SP015

Period of Simple Harmonic Motion

PSPM 2002/2003 SF017/2 No. 4(b)

31. A pendulum consists of a long steel wire and a bob of mass 10 kg. In the early morning,
oscillation period is recorded as 12.0 seconds but after noon the temperature increased
and the oscillation period of the pendulum becomes 13.5 seconds. Calculate the
elongation percentage for the cable of the pendulum. [2 m]

PSPM 2003/2004 SF017/2 No. 4

32. An object of mass 100 kg suspended from a light helix spring is in simple harmonic
motion with period of 1.0 s. What additional mass should be added to the spring so that
the spring will oscillate with a period of 3.0 s? [4 m]

PSPM 2004/2005 SF017/2 No. 4

33. A simple pendulum is suspended from the ceiling of a lift. The period of oscillation T of
the pendulum when the lift is at rest is given by


T  2
g

where  and g are the length and the gravitational acceleration respectively. Explain the
change in the period of the oscillation when the lift is moving
(a) upwards with acceleration a. [2 m]

(b) at constant velocity. [2 m]

PSPM 2007/2008 SF017/2 No. 4

34. A spring with a mass m attached to its end vibrates with a period of 1.5 s. When an
additional mass of 0.8 kg is added to m, the period is 2.2 s. Calculate the value of m.
[4 m]

PSPM 2008/2009 SF017/2 No. 12(c)

35. An astronaut on the moon sets up a simple pendulum of length 0.8 m. The pendulum
executes simple harmonic motion and makes 20 complete cycles in 90 s. Calculate the
acceleration due to gravity of the moon. [2 m]

PSPM 2008/2009 SF017/2 No. 4

36. A spring extends by 4 cm when a 100 g mass is suspended from it. Calculate the period
of oscillation when the mass is allowed to oscillate. [3 m]

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